Electrochemical evaluation of LiZnxMn2−xO4 (x≤0.10) cathode material synthesized by solution combustion method

Abstract

The spinel LiZnxMn2−xO4 (x≤0.10) cathode materials have been synthesized by solution combustion method at 600°C for 3h. The structure and the morphology of LiZnxMn2−xO4 were characterized by X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM), respectively. All the obtained samples were identified as the spinel structure of LiMn2O4, the lattice parameters of samples decreased and the particle size increased as the Zn content increased. The effects of Zn-doping on the electrochemical characteristics of LiMn2O4 were investigated by galvanostatic charge–discharge experiments, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Among them, LiZn0.05Mn1.95O4 particles presented outstanding cycling stability with a capacity retention of 82.9% at a discharge rate of 1C (1C=148mAhg−1) after 500 cycles. Spinel LiZn0.05Mn1.95O4 had reversible cycling performance, revealing that doping LiMn2O4 with Zn improves its electrochemical performance.